Germ-line mutations of KMT2D are associated with Kabuki syndrome, an autosomal dominant disease characterized in part by immunological defects, but without a significant predisposition to lymphomas.23 Somatic mutations of KMT2D are found in the majority of FL9, 10, 12, 14, 16 and less commonly in GCB-like DLBCL.12, 13, 15 These mutations are most commonly small deletions creating frameshifts or nucleotide variants that introduce premature stop codons, indicating that they induce a loss of function. This evidence concerns the gene KMT2D and diffuse large B-cell lymphoma.